The ability to localize sounds is a perceptual achievement with evident biological utility. Localizing sounds in an enclosed space should be particularly difficult due to the interference of acoustic reflections from its boundaries. It is proposed that this situation be explored by conducting experiments in a room bounded by a single sound-reflecting surface that can variously serve as its wall, floor, or ceiling. One set of experiments will examine localization of sounds in the vertical median plane under various room conditions. A second set will be concerned with the contributions that head and body movements make to the localization of sounds in a room. A third set will involve analysis of the binaural time and intensity cues that are available to subjects as they make their localization judgments. Results of these experiments should provide information about the complexities of localizing sounds in a room and about listeners' means of dealing with those complexities. Deficits in the ability to localize sounds are closely associated with schizophrenia and may be differentially manifest in its paranoid and nonparanoid subgroups. A better understanding of the processes of auditory localization, as they operate in normal populations, may help to clarify these clinical deficits. The proposed study is intended to enhance our understanding of auditory localization in enclosed environments.